Piano



G. LUTZ.

PIANO.

APPLICATION FILED FEB. 28, 1919.

PIIIenIedFeb. 24,1920.

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GEORGE LUTZ, OF CAMBRIDGE, MASSACHUSETTS.

` PIANO.

Application filed February 28, 1919. Serial No. 79,730.

T0 all whom 'it may concern.'

Beit known that I, Geenen LUTZ, a citizen of the United States, residing at Cambridge, county of Middlesex, State of Massachusetts, have invented an Improvement in `lPianos, of which the vfollowing description, in connection with the accompanying drawing, is a specification, like characters on the drawing representing like parts.

This invention relates to pianos and has for its object to provide a novel device by which the tension of the sounding board may be regulated whereby a tone of increased fullness and richness' will be produced. j

My improved device may be used in connection with either upright pianos or grand pianos, and it comprises two seat members adapted to be attached to the piano frame, a bridge member adapted to rest against the seat members, and an adjusting screwy carried bythe bridge member and adapted to transmit pressure to the sounding board,l

thereby to increase the tension of the latter.

In order to give an understanding of my invention, I have shown it in the drawings as it might be applied to an upright piano, and I will first describe a selected embodiment thereof, after which the novel features will be pointed out in the appended claims.

Figure l is a view showing the back iraming of an upright piano with the sounding board attached thereto and illustrating my improved tensioirregulating device;

F ig. 2 is a section on the line 2-2, Fig. l;

Fig. 3 is an enlarged perspective view of the foot which rests against the sounding board;

Fig. 4 shows a diierent embodiment oiE the invention.

In the drawings the back framing of an upright piano is indicated generally at i and it comprises in its construction a plural* ity of vertically-extending posts 2 as usual in upright pianos. 3 indicates the sounding board which is of usual construction and is shown as secured to the back framing by having its edges glued thereto, as shown at Il. Associated with the sounding board is the bridge 5 against which the piano strings (not shown) rest.

The above-described parts are or may be all as usual in upright pianos and form no part of my present invention.

As stated above, my invention comprises a novel device adapted to be secured to the .Specification of Letters Patent.

Patented Feb. 24, 1920.

posts 2 of the back framing and constructed to act against the rear face 'of the sounding board 3 thereby to force the rear face out-V wardly so as to produce in the sounding board the desired tension. The device herein shown for a'ccomplishing` this comprises two seat members 6 which are constructed to be secured to two adjacent posts 2, and each of which is provided with a. seat portion 7 that extends laterally from the post, a bridge member 8 adapted to rest against the seat portion and an adjustingscrew 9 screw-threaded through the bridge member 8 and constructed to apply pressure to the back side of the sounding board.

The seat members 6 are each shown as having a body portion which rests against the inside face ot the post 2, and a laterallyextending flange portion l() arranged to rest against the front tace of the post, each seat member being secured to the post by means o1 a suitable screw 11. Nhen the two seat members are thus secured tothe posts, the seat 'portions thereof face each other and form rests or seats to receive the ends of the bridge member 8.

In order to prevent the adjusting screw 9 from injuring the sounding board I propose to interpose a foot member between the adjusting screw andthe sounding board. This foot member is illustrated in Fig. 3 and it will preferably be formed with a wooden facing 12 which rests against the 'inner face of the'sounding board, and a metal backing 1.3 which has a socket or de- Vpression le to receive the end of the adjusting Vscrew 9. The backing 13 is preferably placed at one end of the root and in applying the device to a piano the seat member 6 is so positioned on the posts 2 that the screw will come directly back oft-he bridge 5 at a point about centrally of the sounding board.

.The foot will "also preferably vbe arranged,

as shown in Fig. l, so that it will project below the bridge and bear against the portion of the sounding board beneath the bridge.

When the device is applied to the piano, the bridge member 8 constitutes a nut for the adjusting screw so that by turning the screw the central portion of the sounding board will be forced outwardly, thus placing the sounding board under increased tension. The pressure to which the screw is subjected is transmitted to the posts 2 through the anges 10 of the seat members 'isA to two adjacent posts 2, they might both be placed on the `same post, in which case the bridge member would extend in a vertical rather than a horizontal direction. The particular position in which the seat members are placed will depend somethingupon where it is desired to apply pressure to the sounding board to secure the vdesired results. By suitable modifications the device mayalsobe applied to grand pianos.

I claim:

1. In a piano having the usual back framing including` vertical posts and a sounding board secured thereto, the combination with said posts and sounding board, of two seat members secured to two adjacent posts, a bridge memberl resting on said seat members, and an adjusting pin screw-threaded through the bridge member and adapted vto transmit pressure to the back side of the sounding board.

2. In a piano, the combination with `the usual back framing including vertical posts, of a sounding board having its edges secured to said framing, two seat members se- Y cured to two adjacent posts, a bridge member resting on said seat members, an adjusting'screw screw-threaded through said bridge member, Aand .a foot interposed between the screw and the sounding board.

3. In a piano, the combination with the usual back rra-ming including vertical posts, oi -a sounding board having its edges ksecured to said framing, two seat members secured to two adjacent posts, a bridge member resting on said seat .members, an adjusting screw screw-.threaded through said-bridge member, and a foot interposed between the screw and the sounding board, said foot having 4a wooden face resting against the sounding board and a metal back in which the screw engages.

d. In a piano, the combination with the usual back framing including vertical posts and a sounding board having its edges secured to said frame, of two seat members secured to two adjacent posts, each seat member having a body portion to voverlie the side of the post, a liange engaging the inner face of the post and a laterally-extending seat. portion, a bridge `member having its ends resting on said .seat portions, an adjusting screw screw-threaded through the bridge member, and a 'foot member interposed between the screw and the sounding board.

In testimony whereof I Vhave signed my name to this speciiication.

GEORGE LUTZ. 

